JP2011225764A - Resin film with adhesive and optical laminate using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin film with an adhesive, which is imparted with antistatic properties, does not cause exfoliation even in a test under a severe environment assuming a use in vehicle mounting or the like when adhering to glass, and has an adhesive layer excellent in durability on the surface of the resin film.SOLUTION: The resin film with the adhesive is obtained by forming the adhesive layer in the resin film such as an optical film and a surface protective film. The adhesive layer is formed of an adhesive composition containing 100 pts.wt. of an acrylic resin (A) with a structural unit derived from (meth)acrylic acid ester in a formula (I) as a main component, 0.2 to 8 pts.wt. of a pyridinium salt (B) in a formula (II), and 0.1 to 5 pts.wt. of a crosslinker (C). (In the formula (I), Rdenotes a hydrogen atom or a methyl group, and Rdenotes a 1C-14C alkyl group or aralkyl group which may be replaced with a 1C-10C alkoxy group). (In the formula (II), Rdenotes a linear 12C-16C alkyl group, Rdenotes a hydrogen atom or a methyl group, and X- denotes an ion having a fluorine atom).

Description

  The present invention relates to a resin film having a pressure-sensitive adhesive layer formed thereon. As a resin film targeted in the present invention, for example, an optical film including a polarizing film and / or a retardation film, and a surface opposite to the pressure-sensitive adhesive layer of the optical film are bonded, and the surface is used until use. The surface protection film to protect can be mentioned. The present invention also relates to an optical laminate for liquid crystal display using a resin film on which the pressure-sensitive adhesive layer is formed.

  A polarizing film is mounted on a liquid crystal display device and is widely used. A transparent protective film is laminated on both sides of a polarizer, and an adhesive layer is formed on the surface of at least one protective film. It is distributed in the state where the release film is stuck to. Moreover, a retardation film is laminated on a polarizing film in which a protective film is bonded on both sides of the polarizer to form an elliptically polarizing film, and an adhesive layer / release film is stuck in this order on the retardation film side. A protective film on one side of the polarizer, and a retardation film directly on the other side to form an elliptical polarizing film. The adhesive layer / release film is on the retardation film side. May be stuck in order. Furthermore, an adhesive layer / release film may be stuck in this order on the surface of the retardation film. Prior to bonding to the liquid crystal cell, the release film is peeled off from these polarizing film, elliptical polarizing film, retardation film, etc., and bonded to the liquid crystal cell via the exposed adhesive layer. Such a polarizing film, an elliptically polarizing film, or a retardation film generates static electricity when the release film is peeled off and bonded to a liquid crystal cell.

  As one of the countermeasures, in Japanese Patent No. 3012860 (Patent Document 1), in a polarizing film in which a protective film is laminated on the surface of a polarizer film and an adhesive layer is provided on the surface of the protective film, It has been proposed to use an ion conductive composition composed of an electrolyte salt and an organopolysiloxane and a composition containing an acrylic copolymer. Although the antistatic property is expressed by using the pressure-sensitive adhesive containing such an ion conductive composition, the performance is not necessarily sufficient, and the adhesion durability is also sufficient. There wasn't.

  Therefore, Japanese Patent Publication No. 2004-536940 (Patent Document 2) discloses that an organic salt-based antistatic agent is blended with a pressure-sensitive adhesive (adhesive) to impart antistatic properties to the adhesive. It is disclosed. JP-A-2004-114665 (Patent Document 3) includes a salt composed of a quaternary ammonium cation having a total carbon number of 4 to 20 and a fluorine atom-containing anion in an adhesive, etc. It is described to give. Japanese Patent Application Laid-Open No. 2006-307238 (Patent Document 4) describes that an adhesive contains an ionic liquid that becomes liquid at room temperature (25 ° C.) to prevent charging. Furthermore, JP 2009-79205 A (Patent Document 5) describes a polarizing film coated with an adhesive by adding a specific ionic compound that becomes solid at room temperature (25 ° C.) to the adhesive. It is described that a resin film with a pressure-sensitive adhesive having excellent antistatic properties and durability can be obtained without causing a change with time even if left for a long time.

  On the other hand, an optical film with an adhesive as described above is bonded to a liquid crystal cell on the adhesive layer side to form a liquid crystal display device. In this state, the optical film is placed under high temperature or high temperature and high humidity conditions, or heated. If the cooling is repeated, foaming occurs in the pressure-sensitive adhesive layer with the dimensional change of the optical film, or floats or peels between the optical film and the pressure-sensitive adhesive layer, or between the pressure-sensitive adhesive layer and the liquid crystal cell glass. Therefore, it is required to have excellent durability without causing such problems.

  The high temperature condition to which the liquid crystal display device is exposed varies depending on the application of the liquid crystal display device. An optical film with an adhesive containing an ionic compound as described above as an antistatic agent may exhibit sufficient durability in a test in a general temperature range assuming a TV or a monitor. In a test under a harsher environment assuming an in-vehicle application, floating or peeling still occurred between the pressure-sensitive adhesive layer and the liquid crystal cell glass. In particular, this tendency was remarkable when the moisture permeability of the resin film to which the pressure-sensitive adhesive layer is bonded is low.

  In addition, when exposed to high temperatures, the distribution of residual stress acting on the optical film becomes non-uniform, and stress concentration occurs on the outer periphery of the optical film, resulting in white spots where the outer periphery becomes whitish when displaying black Since the phenomenon may occur or color unevenness may occur, suppression of such white spots and color unevenness is also required. Furthermore, when there is a problem when the optical film with an adhesive is bonded to the liquid crystal cell, the optical film is removed once and then a new film is reattached. A so-called rework property is also required in which the pressure-sensitive adhesive layer is peeled off along with the optical film, and the pressure-sensitive adhesive does not remain on the cell glass and no fogging occurs.

  On the other hand, a surface protective film is generally bonded to an optical film that is a protected body through an adhesive formed on one side thereof, and is used to prevent scratches or dirt generated during processing or transportation of the protected body. It is done. For example, an optical film such as a polarizing film or a retardation film for application to a liquid crystal display device is on the side opposite to the adhesive layer for bonding to the liquid crystal cell described above for the purpose of preventing scratches and dirt. The surface protective film is distributed in a state where the surface protective film is bonded to the surface. This surface protective film is peeled and removed after the optical film is bonded to the liquid crystal cell. When the surface film is peeled off, static electricity is generated, and when a voltage is applied to the liquid crystal cell with the static electricity remaining, the liquid crystal molecules The surface protective film is subjected to various antistatic treatments because of the problem that the orientation of the film is impaired or the panel is damaged.

Japanese Patent No. 3012860 (= Japanese Patent Laid-Open No. 6-313807) Japanese translation of PCT publication No. 2004-536940 (= WO 2003/011958) JP 2004-114665 A JP 2006-307238 A JP 2009-79205 A

  The problem of the present invention is that the antistatic property is imparted, and the adhesive layer is excellent in durability, and does not peel off even in a test under a harsh environment assuming an in-vehicle use or the like when bonded to glass. It is providing the resin film with an adhesive which provided this on the surface of the resin film. As a result of intensive studies to solve such problems, the present inventors have found that an ionic compound having an alkylpyridinium skeleton, in particular, the number of carbon atoms of the alkyl group, with respect to a pressure-sensitive adhesive mainly composed of an acrylic resin. Adhesive with excellent durability under harsh conditions while having antistatic properties by blending a pyridinium salt having a certain range within this range and providing this composition as an adhesive layer on the surface of the resin film It discovered that the resin film with an agent was obtained and reached | attained this invention.

  That is, according to the present invention, the pressure-sensitive adhesive layer is formed on at least one surface of the resin film, and the pressure-sensitive adhesive layer contains the following components (A), (B) and (C). The resin film with an adhesive currently formed from is provided.

  (A) The following formula (I)

(In the formula, R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents a C 1-14 alkyl group or an aralkyl group, each of which may be substituted with a C 1-10 alkoxy group)
100 parts by weight of an acrylic resin whose main component is a structural unit derived from a (meth) acrylic acid ester represented by
(B) The following formula (II)

(Wherein R ₃ represents a linear alkyl group having 12 to 16 carbon atoms, R ₄ represents a hydrogen atom or a methyl group, and X ⁻ represents an ion having a fluorine atom)
0.2 to 8 parts by weight of a pyridinium salt represented by the formula: (C) 0.1 to 5 parts by weight of a crosslinking agent.

  Thus, in this invention, while providing an antistatic property to the adhesive layer formed from the composition containing an acrylic resin (A) and a crosslinking agent (C), the resin film provided with the adhesive layer As an antistatic agent with excellent durability even when tested in harsh environments assuming automotive applications, etc., it is ionic and has a specific alkyl chain. It has been found that the pyridinium salt (B) possessed is particularly effective.

  In the resin film with an adhesive, the acrylic resin (A) includes one olefinic double bond in the molecule in addition to the structural unit derived from the (meth) acrylic acid ester represented by the formula (I). It may further have a structural unit derived from an unsaturated monomer having at least one aromatic ring.

The resin film provided with the pressure-sensitive adhesive layer as described above can be an optical film including a polarizing film and / or a retardation film. In particular, when the resin film includes a retardation film, and the moisture permeability at a temperature of 40 ° C. and a relative humidity of 90% is 300 g / (m ² · 24 hr) or less, for example, the retardation film Is advantageous when it is composed of a cycloolefin-based resin.

  Moreover, the resin film to which the above-mentioned pressure-sensitive adhesive layer is applied may be a surface protective film that is bonded to the surface of the optical film opposite to the pressure-sensitive adhesive layer and protects the surface until use.

  When a resin film is an optical film, it can laminate | stack on a glass substrate at the adhesive layer side, and can be set as the optical laminated body for liquid crystal displays. Then, according to this invention, the optical laminated body formed by laminating | stacking the optical film with an adhesive in which said adhesive layer was formed in the optical film on the glass substrate by the adhesive layer side is also provided.

  When the resin film with the pressure-sensitive adhesive of the present invention is bonded to glass through the pressure-sensitive adhesive layer, it is excellent in durability under a harsh environment assuming on-vehicle use. Whether the resin film with an adhesive is used as a surface protective film or an optical film, the charging of the optical member can be effectively suppressed.

  This resin film with an adhesive provides an optical laminate for liquid crystal display, for example, by constituting a resin film with an optical film and laminating it on a glass substrate of a liquid crystal cell. In this optical laminate, the pressure-sensitive adhesive layer absorbs and relaxes stress caused by dimensional changes of the optical film and the glass substrate under wet heat conditions, so that local stress concentration is reduced and the pressure-sensitive adhesive layer floats on the glass substrate. And peeling are suppressed. In addition, since optical defects due to non-uniform stress distribution are prevented, white spots are suppressed. Furthermore, after laminating the resin film with the adhesive once on the glass substrate, if there is any defect, even if the resin film is peeled off from the glass substrate together with the adhesive, the adhesive residue or the like on the surface of the glass substrate after peeling. Clouding is less likely to occur, and it can be used again as a glass substrate, resulting in excellent reworkability.

  Moreover, this resin film with an adhesive can be bonded to the surface of an optical film and used as a surface protective film that protects the surface until use. Also in this case, it gives an excellent antistatic effect, for example, occurs when the surface protective film is peeled off after the optical film is bonded to the liquid crystal cell via the pressure-sensitive adhesive layer opposite to the surface protective film. Can reduce static electricity.

Hereinafter, the present invention will be described in detail. The resin film with an adhesive of the present invention is one in which an adhesive layer is formed on at least one side of the resin film, and the adhesive layer is
(A) an acrylic resin mainly composed of a structural unit derived from the (meth) acrylic acid ester represented by the formula (I),
(B) It has an alkylpyridinium skeleton, and is formed from a pressure-sensitive adhesive composition containing a pyridinium salt represented by the formula (II) and (C) a crosslinking agent. First, each component which comprises an adhesive composition is demonstrated.

[Acrylic resin (A)]
In the resin film with pressure-sensitive adhesive of the present invention, the acrylic resin (A) used in the pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer is a structural unit derived from the (meth) acrylic acid ester represented by the formula (I). Although it is a polymer having a main component, it is generally a copolymer including other structural units, particularly monomers having polar functional groups, preferably structural units derived from (meth) acrylic acid-based compounds having polar functional groups. Consists of a polymer. Examples of the polar functional group include a free carboxyl group, a hydroxyl group, an amino group, and a heterocyclic group including an epoxy ring. Furthermore, monomers other than the formula (I) having no polar functional group can be copolymerized. Examples of copolymer components that can be suitably used include a monomer having one olefinic double bond and at least one aromatic ring in the molecule, preferably a (meth) acrylic acid compound having an aromatic ring. Can do. In the present specification, (meth) acrylic acid means that either acrylic acid or methacrylic acid may be used, and “(meth)” in the case of (meth) acrylate or the like has the same meaning. .

In the formula (I), which is the main structural unit of the acrylic resin (A), R ₁ is a hydrogen atom or a methyl group, and R ₂ is an alkyl group or aralkyl group having 1 to 14 carbon atoms, preferably an alkyl group. is there. In the alkyl group or aralkyl group represented by R ₂ , a hydrogen atom in each group may be substituted with an alkoxy group having 1 to 10 carbon atoms.

  Specific examples of the (meth) acrylic acid ester represented by the formula (I) include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-octyl acrylate, and lauryl acrylate, Linear alkyl acrylate ester; branched alkyl acrylate ester such as isobutyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-methacrylate Examples include linear alkyl methacrylates such as butyl, n-octyl methacrylate and lauryl methacrylate; branched alkyl esters such as isobutyl methacrylate, 2-ethylhexyl methacrylate and isooctyl methacrylate. Is done.

When R ₂ is an alkyl group substituted with an alkoxy group, that is, when R ₂ is an alkoxyalkyl group, the (meth) acrylic acid ester represented by the formula (I) is specifically acrylic acid. Examples include 2-methoxyethyl, ethoxymethyl acrylate, 2-methoxyethyl methacrylate, ethoxymethyl methacrylate, and the like. Specific examples of the (meth) acrylic acid ester represented by the formula (I) when R ₂ is an aralkyl group include benzyl acrylate and benzyl methacrylate.

  These (meth) acrylic acid esters can be used alone or in combination. Among them, n-butyl acrylate is preferably used. Specifically, it is preferable that n-butyl acrylate is 50% by weight or more of all monomers constituting the acrylic resin (A). . Of course, in addition to n-butyl acrylate, other (meth) acrylic acid esters corresponding to the formula (I) may be used in combination.

  In addition to the (meth) acrylic acid ester represented by the formula (I), a monomer other than the formula (I) having one olefinic double bond and at least one aromatic ring in the molecule, for example, When a (meth) acrylic acid compound having an aromatic ring is copolymerized, preferred examples of the (meth) acrylic acid compound having an aromatic ring include phenoxyethyl group-containing compounds represented by the following formula (III) ( There are (meth) acrylic acid esters.

In the formula, R ₅ represents a hydrogen atom or a methyl group, n represents an integer of 1 to 8, and R ₆ represents a hydrogen atom, an alkyl group, an aralkyl group, or an aryl group. When R ₆ is an alkyl group, the carbon number can be about 1 to 9, and when it is an aralkyl group, the carbon number is about 7 to 11, and when it is an aryl group, the carbon number is It can be about 6-10.

Examples of the alkyl group having 1 to 9 carbon atoms constituting R ₆ in the formula (III) include methyl, butyl and nonyl, and examples of the aralkyl group having 7 to 11 carbon atoms include benzyl, phenethyl and naphthylmethyl. Examples of the aryl group having 6 to 10 carbon atoms include phenyl, tolyl, and naphthyl.

  Specific examples of the phenoxyethyl group-containing (meth) acrylic acid ester represented by the formula (III) are: (meth) acrylic acid 2-phenoxyethyl, (meth) acrylic acid 2- (2-phenoxyethoxy) ethyl, ethylene There are (meth) acrylic acid esters of oxide-modified nonylphenol, 2- (o-phenylphenoxy) ethyl (meth) acrylate, and the like. These phenoxyethyl group-containing (meth) acrylic acid esters may be used alone or in combination of a plurality of different ones.

  Among these, (meth) acrylic acid 2-phenoxyethyl, (meth) acrylic acid 2- (o-phenylphenoxy) ethyl or (meth) acrylic acid 2- (2-phenoxyethoxy) ethyl is used as an acrylic resin (A). It is preferably used as one of the aromatic ring-containing monomers constituting It is also effective to use these monomers in combination.

  Examples of monomers having a polar functional group include monomers having a free carboxyl group such as acrylic acid, methacrylic acid, and β-carboxyethyl acrylate; (meth) acrylic acid 2-hydroxyethyl, (meth) Monomers having a hydroxyl group such as 2-hydroxypropyl acrylate, 2- or 3-chloro-2-hydroxypropyl (meth) acrylate, and diethylene glycol mono (meth) acrylate; acryloylmorpholine, vinylcaprolactam, N-vinyl- Heterocyclic groups such as 2-pyrrolidone, tetrahydrofurfuryl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, glycidyl (meth) acrylate, and 2,5-dihydrofuran; Have Mer; N, such as N- dimethylaminoethyl (meth) acrylate, and the like monomers having different amino group and heterocyclic. These monomers having polar functional groups may be used alone or in combination with a plurality of different monomers.

  Among these, it is preferable to use a monomer having a hydroxyl group as one of polar functional group-containing monomers constituting the acrylic resin (A). In addition to the monomer having a hydroxyl group, it is also effective to use a monomer having another polar functional group, for example, a monomer having a free carboxyl group.

  The acrylic resin (A) used in the pressure-sensitive adhesive composition is usually a structural unit derived from the (meth) acrylic acid ester represented by the formula (I) based on the amount of the entire solid content, usually 60 to 99. 9.9% by weight, preferably 80 to 99.6% by weight, and the structural unit derived from the monomer other than the formula (I) having an aromatic ring is usually 0 to 40% by weight, preferably Is contained in a proportion of 6 to 12% by weight, and the structural unit derived from a monomer having a polar functional group is usually in a proportion of 0.1 to 20% by weight, preferably 0.4 to 10% by weight. Contains.

  The acrylic resin (A) used in the present invention is a monomer having a (meth) acrylic acid ester of the formula (I) described above, a monomer other than the formula (I) having an aromatic ring, and a polar functional group. In addition to the body, a structural unit derived from a monomer other than those may be included. Examples of these include structural units derived from (meth) acrylic acid esters having an alicyclic structure in the molecule, structural units derived from styrene monomers, structural units derived from vinyl monomers, molecules Examples thereof include a structural unit derived from a monomer having a plurality of (meth) acryloyl groups, a (meth) acrylamide derivative, and the like.

  The alicyclic structure is a cycloparaffin structure having usually 5 or more carbon atoms, preferably about 5 to 7 carbon atoms. Specific examples of the acrylate ester having an alicyclic structure include isobornyl acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, cyclododecyl acrylate, methyl cyclohexyl acrylate, trimethyl cyclohexyl acrylate, tert-butyl acrylate Specific examples of methacrylic acid esters having an alicyclic structure include cyclohexyl, α-ethoxyacrylic acid cyclohexyl, cyclohexyl phenyl acrylate, etc. Specific examples of methacrylic acid ester having an alicyclic structure include isobornyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, methacrylic acid. Such as cyclododecyl, methyl cyclohexyl methacrylate, trimethyl cyclohexyl methacrylate, tert-butyl cyclohexyl methacrylate, cyclohexyl phenyl methacrylate And so on.

  Examples of the styrenic monomer include styrene, alkyl styrene such as methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, octyl styrene; fluoro Halogenated styrene such as styrene, chlorostyrene, bromostyrene, dibromostyrene, iodostyrene; and nitrostyrene, acetylstyrene, methoxystyrene, divinylbenzene and the like.

  Examples of vinyl monomers include: vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate; vinyl halides such as vinyl chloride and vinyl bromide; vinylidene chloride Examples thereof include vinylidene halides; nitrogen-containing aromatic vinyls such as vinylpyridine, vinylpyrrolidone and vinylcarbazole; conjugated diene monomers such as butadiene, isoprene and chloroprene; and acrylonitrile and methacrylonitrile.

  As monomers having a plurality of (meth) acryloyl groups in the molecule, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di ( 2 (meth) acryloyl groups in the molecule such as (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate And a monomer having three (meth) acryloyl groups in the molecule, such as trimethylolpropane tri (meth) acrylate.

  As (meth) acrylamide derivatives, N-methylol (meth) acrylamide, 2-hydroxyethyl (meth) acrylamide, 3-hydroxypropyl (meth) acrylamide, 4-hydroxybutyl (meth) acrylamide, 5-hydroxypentyl (meth) Acrylamide, 6-hydroxyhexyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-propoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N -Dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-dimethylaminopropyl (meth) acrylamide, N- (1,1-dimethyl- Oxobutyl) (meth) acrylamide, etc. can be mentioned N- [2- (2-oxo-1-imidazolidinyl) ethyl] (meth) acrylamide, 2-acryloylamino-2-methyl-1-propanesulfonic acid.

  Monomers other than the (meth) acrylic acid ester of the formula (I), the monomer other than the formula (I) having an aromatic ring, and the monomer having a polar functional group may be used alone or in combination of two or more. Can be used. In the acrylic resin (A) used for the pressure-sensitive adhesive, a monomer other than the (meth) acrylic acid ester of the formula (I), the monomer other than the formula (I) having an aromatic ring and the monomer having a polar functional group. The structural unit derived from the monomer is usually contained in a proportion of 0 to 20 parts by weight, preferably 0 to 10 parts by weight, based on the total amount of the solid content of the resin.

  The resin component of the pressure-sensitive adhesive composition has the structural unit derived from the (meth) acrylic acid ester represented by the formula (I) as a main component and the structural unit derived from the monomer having a polar functional group. And optionally two or more kinds of acrylic resins containing structural units derived from monomers other than the formula (I) having an aromatic ring. Furthermore, an acrylic resin different from the acrylic resin, specifically, for example, an acrylic resin having a structural unit derived from the (meth) acrylic ester of formula (I) and having no polar functional group is mixed with the acrylic resin. It may be what you did. An acrylic resin containing a structural unit derived from a monomer having a polar functional group, the main component of which is a structural unit derived from the (meth) acrylic acid ester of the formula (I) is 60% by weight or more of the whole acrylic resin. Further, it is preferably 80% by weight or more.

  An acrylic resin containing a structural unit derived from a monomer having a polar functional group, the main component of which is a structural unit derived from the (meth) acrylic acid ester of the formula (I) is obtained by gel permeation chromatography (GPC). The weight average molecular weight (Mw) in terms of standard polystyrene is preferably in the range of 1 million to 2 million. When the weight average molecular weight in terms of standard polystyrene is 1 million or more, the adhesiveness under high temperature and high humidity is improved, and the possibility of occurrence of floating or peeling between the glass substrate and the pressure-sensitive adhesive layer is reduced. And reworkability tends to be improved. Further, when the weight average molecular weight is 2 million or less, even when the pressure-sensitive adhesive layer is bonded to the optical film, even if the dimension of the optical film changes, the pressure-sensitive adhesive layer follows the dimensional change and fluctuates. Therefore, it is preferable because there is no difference between the brightness of the peripheral edge of the liquid crystal cell and the brightness of the center, and white spots and color unevenness tend to be suppressed. The molecular weight distribution represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is usually in the range of about 2 to 10.

  This acrylic resin can be composed only of a relatively high molecular weight as described above, or can be composed of a mixture of an acrylic resin different from the acrylic resin in addition to the acrylic resin. Examples of the acrylic resin that can be used as a mixture include, for example, a structural unit derived from the (meth) acrylic acid ester represented by the formula (I) as a main component and a weight average molecular weight in the range of 50,000 to 300,000. Can be mentioned.

  Acrylic resin (a mixture of two or more when combining two or more) is a solution prepared by dissolving it in ethyl acetate to a solid content concentration of 20% by weight. -It is preferable to show the viscosity of s. If the viscosity at this time is 20 Pa · s or less, the adhesiveness under high temperature and high humidity is improved, and the possibility of floating or peeling between the glass substrate and the pressure-sensitive adhesive layer tends to be reduced. Moreover, it is preferable because reworkability tends to be improved. Viscosity can be measured with a Brookfield viscometer.

  The acrylic resin constituting the pressure-sensitive adhesive composition can be produced by various known methods such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a suspension polymerization method. In the production of this acrylic resin, a polymerization initiator is usually used. The polymerization initiator is used in an amount of about 0.001 to 5 parts by weight with respect to a total of 100 parts by weight of all monomers used in the production of the acrylic resin.

  As the polymerization initiator, a thermal polymerization initiator, a photopolymerization initiator, or the like is used. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone. Examples of the thermal polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl-2,2'-azobis (2-methylpropio) Azo) compounds such as 2,2'-azobis (2-hydroxymethylpropionitrile); lauryl peroxide, tert-butyl hydroperoxide, benzoyl peroxide, tert-butyl peroxybenzoate, cumene hydroperoxide , Diisopropyl peroxydicarbonate, dipropyl peroxydicarbonate, tert-butyl peroxy Organic peroxides such as neodecanoate, tert-butyl peroxypivalate, (3,5,5-trimethylhexanoyl) peroxide; inorganic peroxides such as potassium persulfate, ammonium persulfate and hydrogen peroxide Can do. A redox initiator using a peroxide and a reducing agent in combination can also be used as the polymerization initiator.

  As a method for producing the acrylic resin, the solution polymerization method is preferable among the methods shown above. A specific example of the solution polymerization method will be described. A desired monomer and an organic solvent are mixed, and a thermal polymerization initiator is added in a nitrogen atmosphere, and the temperature is about 40 to 90 ° C., preferably 60 to 80. A method of stirring at about 0 ° C. for about 3 to 10 hours can be mentioned. Moreover, in order to control reaction, you may add a monomer and a thermal-polymerization initiator continuously or intermittently during superposition | polymerization, or may be added in the state melt | dissolved in the organic solvent. Examples of the organic solvent include aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propyl alcohol and isopropyl alcohol; acetone, methyl ethyl ketone, and methyl isobutyl ketone. Ketones such as can be used.

[Pyridinium salt (B)]
In the present invention, in addition to the acrylic resin (A) as described above, a pyridinium salt (B) represented by the above formula (II) having an alkylpyridinium skeleton is used as an antistatic agent.

The cation component constituting the pyridinium salt (B) of the formula (II) is an N-alkylpyridinium cation, and R in the formula (II) has a durability when bonded to glass via an adhesive layer. _The linear alkyl group represented by ₃ has 12 to 16 carbon atoms. Specifically, this cation component is one of those listed below.

N-dodecylpyridinium ion,
N-tridecylpyridinium ion,
N-tetradecylpyridinium ion,
N-pentadecylpyridinium ion,
N-hexadecylpyridinium ion,
N-dodecyl-4-methylpyridinium ion,
N-tridecyl-4-methylpyridinium ion,
N-tetradecyl-4-methylpyridinium ion,
N-pentadecyl-4-methylpyridinium ion,
N-hexadecyl-4-methylpyridinium ion.

On the other hand, the anion component X ⁻ constituting the pyridinium salt (B) of the formula (II) is an ion having a fluorine atom because it gives an ionic compound having excellent antistatic performance. Specifically, this anion component can be as follows, for example.

Fluorine ions [F ^-],
Tetrafluoroborate ion [BF ₄ ⁻ ],
Hexafluorophosphate ion [PF ₆ ⁻ ],
Trifluoroacetate ion [CF ₃ COO ⁻ ],
Trifluoromethanesulfonate ion [CF ₃ SO ₃ ⁻ ],
Bis (fluorosulfonyl) imide ion [(FSO ₂ ) ₂ N ⁻ ],
Bis (trifluoromethanesulfonyl) imide ion [(CF ₃ SO ₂ ) ₂ N ⁻ ],
Tris (trifluoromethanesulfonyl) methanide ion [(CF ₃ SO ₂ ) ₃ C ⁻ ],
Hexafluoroarsenate ion [AsF ₆ ⁻ ],
Hexafluoroantimonate ion [SbF ₆ ⁻ ],
Hexafluoroniobate ion [NbF ₆ ⁻ ],
Hexafluorotantalate ion [TaF ₆ ⁻ ],
(Poly) hydrofluorofluoride ion [F (HF) _n ⁻ ] (n is about 1 to 3),
Perfluorobutanesulfonate ion [C ₄ F ₉ SO ₃ ⁻ ],
Bis (pentafluoroethanesulfonyl) imide ion [(C ₂ F ₅ SO ₂ ) ₂ N ⁻ ],
Perfluorobutanoate ion [C ₃ F ₇ COO ⁻ ],
(Trifluoromethanesulfonyl) (trifluoromethanecarbonyl) imide ion [(CF ₃ SO ₂ ) (CF ₃ CO) N ⁻ ] and the like.

  The specific example of the pyridinium salt (B) used for this invention can be suitably selected from the combination of the said cation component and an anion component. Specific examples of the compound that is a combination of a cation component and an anion component include the following.

N-dodecylpyridinium hexafluorophosphate,
N-tetradecylpyridinium hexafluorophosphate,
N-hexadecylpyridinium hexafluorophosphate,
N-dodecyl-4-methylpyridinium hexafluorophosphate,
N-tetradecyl-4-methylpyridinium hexafluorophosphate,
N-hexadecyl-4-methylpyridinium hexafluorophosphate,
N-dodecylpyridinium bis (fluorosulfonyl) imide,
N-tetradecylpyridinium bis (fluorosulfonyl) imide,
N-hexadecylpyridinium bis (fluorosulfonyl) imide,
N-dodecyl-4-methylpyridinium bis (fluorosulfonyl) imide,
N-tetradecyl-4-methylpyridinium bis (fluorosulfonyl) imide,
N-hexadecyl-4-methylpyridinium bis (fluorosulfonyl) imide,
N-dodecylpyridinium bis (trifluoromethanesulfonyl) imide,
N-tetradecylpyridinium bis (trifluoromethanesulfonyl) imide,
N-hexadecylpyridinium bis (trifluoromethanesulfonyl) imide,
N-dodecyl-4-methylpyridinium bis (trifluoromethanesulfonyl) imide,
N-tetradecyl-4-methylpyridinium bis (trifluoromethanesulfonyl) imide,
N-hexadecyl-4-methylpyridinium bis (trifluoromethanesulfonyl) imide and the like.

The pyridinium salt of the formula (II) is characterized in that the alkyl group represented by R ₃ is a long chain, but its production itself can be carried out according to a general pyridinium salt. For example, the following formula:

An alkylpyridinium bromide corresponding to (wherein R ₃ and R ₄ are as defined above in formula (II)) and a formula: LiX ⁻ (wherein X ⁻ is as defined above in formula (II)). The pyridinium salt of formula (II) by an ion exchange reaction with the lithium salt corresponding to the formula (II), followed by washing with water, transferring the resulting lithium bromide to the aqueous phase and recovering the organic phase. Can be manufactured. These pyridinium salts (B) can be used alone or in combination of two or more. Of course, examples of the pyridinium salt (B) are not limited to the compounds listed above.

  The pyridinium salt (B) of the formula (II) is in a ratio of 0.2 to 8 parts by weight with respect to 100 parts by weight of the solid content of the acrylic resin (A) (the total when two or more are used). Contain. When the pyridinium salt (B) is contained in an amount of 0.2 part by weight or more based on 100 parts by weight of the solid content of the acrylic resin (A), the antistatic performance is improved, and the amount is 8 parts by weight or less. And it is preferable because it is easy to maintain durability. The amount of the pyridinium salt (B) relative to 100 parts by weight of the acrylic resin (A) may be in the range of 0.2 to 6 parts by weight, preferably 0.5 parts by weight or more and 3 parts by weight or less. It is.

[Crosslinking agent (C)]
A crosslinking agent (C) is blended with the acrylic resin (A) and pyridinium salt (B) as described above to obtain a pressure-sensitive adhesive composition. The crosslinking agent (C) is a compound that reacts with a structural unit derived from the polar functional group-containing monomer in the acrylic resin (A) to crosslink the acrylic resin. Specific examples include isocyanate compounds, epoxy compounds, aziridine compounds, metal chelate compounds, and the like. Among these, the isocyanate compound, the epoxy compound, and the aziridine compound have at least two functional groups that can react with the polar functional group in the acrylic resin (A) in the molecule.

  Isocyanate compounds are compounds having at least two isocyanato groups (-NCO) in the molecule, such as tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, Examples thereof include hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, and triphenylmethane triisocyanate. In addition, adducts obtained by reacting these isocyanate compounds with polyols such as glycerol and trimethylolpropane, and those obtained by converting isocyanate compounds into dimers, trimers, and the like can also be used as crosslinking agents for pressure-sensitive adhesives. Two or more isocyanate compounds can be mixed and used.

  The epoxy compound is a compound having at least two epoxy groups in the molecule, for example, bisphenol A type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether. 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, N, N-diglycidylaniline, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis ( N, N'-diglycidylaminomethyl) cyclohexane and the like. Two or more types of epoxy compounds can be mixed and used.

  An aziridine-based compound is a compound having at least two skeletons of a three-membered ring composed of one nitrogen atom and two carbon atoms, also called ethyleneimine, for example, diphenylmethane-4,4′-bis ( 1-aziridinecarboxamide), toluene-2,4-bis (1-aziridinecarboxamide), triethylenemelamine, isophthaloylbis-1- (2-methylaziridine), tris-1-aziridinylphosphine oxide, hexamethylene Examples include -1,6-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, and the like.

  Examples of the metal chelate compound include compounds in which acetylacetone or ethyl acetoacetate is coordinated to a polyvalent metal such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium. Can be mentioned.

  Among these crosslinking agents, isocyanate compounds, particularly xylylene diisocyanate, tolylene diisocyanate or hexamethylene diisocyanate, or adducts obtained by reacting these isocyanate compounds with polyols such as glycerol and trimethylolpropane, and isocyanate compounds A dimer, a trimer or the like, a mixture of these isocyanate compounds, or the like is preferably used. Preferred isocyanate compounds include tolylene diisocyanate, adducts obtained by reacting tolylene diisocyanate with polyol, tolylene diisocyanate dimers, and tolylene diisocyanate trimers, hexamethylene diisocyanate, hexamethylene diisocyanate. Examples include adducts reacted with polyols, dimers of hexamethylene diisocyanate, and trimers of hexamethylene diisocyanate.

  A crosslinking agent (C) is mix | blended in the ratio of 0.1-5 weight part with respect to 100 weight part (A total of those when using 2 or more types) of acrylic resin (A). The amount of the crosslinking agent (C) relative to 100 parts by weight of the acrylic resin (A) is preferably 0.1 parts by weight or more because the durability of the pressure-sensitive adhesive layer tends to be improved, and is 5 parts by weight or less. And, when the optical film with a pressure-sensitive adhesive is applied to a liquid crystal display device, white spots are not noticeable.

[Silane compound (D)]
When the resin film with the pressure-sensitive adhesive of the present invention is bonded to a glass substrate on the pressure-sensitive adhesive layer side, the pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer improves the adhesion between the pressure-sensitive adhesive layer and the glass substrate. Therefore, it is preferable to contain the silane compound (D), and it is particularly preferable to contain the silane compound in the acrylic resin before blending the crosslinking agent.

  Examples of the silane compound (D) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- ( 2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxy (Cyclohexyl) ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimeth Shishiran, 3-glycidoxypropyl triethoxysilane, 3-glycidoxypropyl dimethoxymethyl silane, such as 3-glycidoxypropyl ethoxy dimethyl silane. Two or more silane compounds may be used.

  The silane compound may be of a silicone oligomer type. When the silicone oligomer is shown in the form of a (monomer) oligomer, for example, the following can be mentioned.

3-mercaptopropyltrimethoxysilane-tetramethoxysilane copolymer,
3-mercaptopropyltrimethoxysilane-tetraethoxysilane copolymer,
3-mercaptopropyltriethoxysilane-tetramethoxysilane copolymer,
A copolymer containing mercaptopropyl groups, such as a 3-mercaptopropyltriethoxysilane-tetraethoxysilane copolymer;

Mercaptomethyltrimethoxysilane-tetramethoxysilane copolymer,
Mercaptomethyltrimethoxysilane-tetraethoxysilane copolymer,
Mercaptomethyltriethoxysilane-tetramethoxysilane copolymer,
A copolymer containing a mercaptomethyl group, such as a mercaptomethyltriethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,
3-methacryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,
3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,
3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,
3-methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-methacryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,
Copolymers containing methacryloyloxypropyl groups, such as 3-methacryloxyyl propylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,
3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,
3-acryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,
3-acryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,
3-acryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-acryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-acryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,
A copolymer containing acryloyloxypropyl groups, such as 3-acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

Vinyltrimethoxysilane-tetramethoxysilane copolymer,
Vinyltrimethoxysilane-tetraethoxysilane copolymer,
Vinyltriethoxysilane-tetramethoxysilane copolymer,
Vinyltriethoxysilane-tetraethoxysilane copolymer,
Vinylmethyldimethoxysilane-tetramethoxysilane copolymer,
Vinylmethyldimethoxysilane-tetraethoxysilane copolymer,
Vinylmethyldiethoxysilane-tetramethoxysilane copolymer,
A vinyl group-containing copolymer, such as vinylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer,
3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer,
3-aminopropyltriethoxysilane-tetramethoxysilane copolymer,
3-aminopropyltriethoxysilane-tetraethoxysilane copolymer,
3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer,
Amino group-containing copolymers such as 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer.

  These silane-based compounds are often liquids. The compounding amount of the silane compound in the pressure-sensitive adhesive is usually about 0.01 to 10 parts by weight with respect to 100 parts by weight of the solid content of the acrylic resin (A) (when two or more kinds are used), preferably Is used in a proportion of 0.05 to 5 parts by weight. When the amount of the silane compound relative to 100 parts by weight of the acrylic resin is 0.01 parts by weight or more, the adhesiveness between the pressure-sensitive adhesive layer and the glass substrate is improved. Moreover, it is preferable for the amount to be 10 parts by weight or less because the silane compound tends to be suppressed from bleeding out from the pressure-sensitive adhesive layer.

[Other components constituting the pressure-sensitive adhesive composition]
The pressure-sensitive adhesive composition described above may further contain a crosslinking catalyst, weathering stabilizer, tackifier, plasticizer, softener, dye, pigment, inorganic filler, resin other than the acrylic resin (A), and the like. It is also useful to blend an ultraviolet curable compound into the pressure-sensitive adhesive composition and to cure it by irradiating with ultraviolet rays after forming the pressure-sensitive adhesive layer to form a harder pressure-sensitive adhesive layer. Among them, if a crosslinking catalyst is blended with the crosslinking agent in the pressure-sensitive adhesive composition, the pressure-sensitive adhesive layer can be prepared by aging in a short time, and in the resulting resin film with a pressure-sensitive adhesive, between the resin film and the pressure-sensitive adhesive layer. It is possible to suppress the occurrence of floating or peeling or foaming in the pressure-sensitive adhesive layer, and the reworkability may be further improved. Examples of the crosslinking catalyst include amine compounds such as hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, polyamino resin, and melamine resin. When an amine compound is blended in the pressure-sensitive adhesive composition as a crosslinking catalyst, an isocyanate compound is suitable as the crosslinking agent.

  Each of these components constituting the pressure-sensitive adhesive is made into a pressure-sensitive adhesive composition in a state dissolved in a solvent, and is applied onto a suitable substrate and dried to form a pressure-sensitive adhesive layer.

[Resin film with adhesive]
The resin film with a pressure-sensitive adhesive of the present invention is obtained by providing a pressure-sensitive adhesive layer formed from the above pressure-sensitive adhesive composition on at least one surface of a resin film. The resin film used here is an optical film including a polarizing film or a retardation film, a surface protective film used for the purpose of protecting the surface from scratches and dirt, etc. Is mentioned.

  A polarizing film is an optical film having a function of emitting polarized light with respect to incident light such as natural light. The polarizing film absorbs linearly polarized light having a vibration surface in a certain direction incident on the film surface, and transmits linearly polarized light having a vibration surface perpendicular to the polarizing surface, and in a certain direction incident on the film surface. There are a polarizing separation film having a property of reflecting linearly polarized light having a vibration surface and transmitting linearly polarized light having a vibration surface orthogonal thereto, and an elliptically polarizing film in which a polarizing film and a retardation film described later are laminated. As a suitable specific example of a polarizing film, particularly a linear polarizing film (sometimes called a polarizer or a polarizer film), a dichroic dye such as iodine or a dichroic dye is added to a uniaxially stretched polyvinyl alcohol resin film. Are adsorbed and oriented.

  A retardation film is an optical film exhibiting optical anisotropy, for example, polyvinyl alcohol, polycarbonate, polyester, polyarylate, polyimide, polyolefin, polycycloolefin, polystyrene, polysulfone, polyethersulfone, polyvinylidene fluoride. A stretched film obtained by stretching a polymer film composed of ride / polymethylmethacrylate, liquid crystal polyester, acetylcellulose, saponified ethylene-vinyl acetate copolymer, polyvinyl chloride, etc. by about 1.0 to 6 times. Can be mentioned. Among these, a polymer film obtained by uniaxially stretching or biaxially stretching a polycarbonate film or a cycloolefin-based resin film is preferable. Although there exist what is called a uniaxial phase difference film, a wide viewing angle phase difference film, a low photoelasticity phase difference film, etc., it is applicable to all.

  The cycloolefin resin is, for example, a thermoplastic resin having a cycloolefin monomer unit represented by norbornene, tetracyclododecene (also known as dimethanooctahydronaphthalene) or a derivative thereof. In addition to the ring-opened polymer of the present invention and the hydrogenated product of the ring-opened copolymer using two or more kinds of cycloolefins, addition copolymerization of cycloolefin with a chain olefin or an aromatic compound having a vinyl group It may be a coalescence. In addition, a polar group may be introduced.

Commercially available thermoplastic cycloolefin resins are, for example, produced by TOPAS ADVANCED POLYMERS GmbH, Germany, and sold by "TOPAS" and JSR, which are sold by Polyplastics in Japan. “ARTON”, “ZEONEX” and “ZEONOR” sold by Nippon Zeon Co., Ltd., “Apel” sold by Mitsui Chemicals, etc. )

  In forming such a cycloolefin-based resin into a film, a known film forming method such as a solvent casting method or a melt extrusion method is appropriately used for film formation. A formed cycloolefin-based resin film and a cycloolefin-based resin film further stretched and provided with a phase difference are also commercially available. For example, "Arton Film" sold by JSR Corporation, "Zeonor Film" sold by Nippon Zeon Corporation, "Essina" and "SCA40" sold by Sekisui Chemical Co., Ltd. (Both are trade names) and these can be used preferably.

When an adhesive layer is formed on an optical film including a retardation film and is bonded to glass via the adhesive layer, if the moisture permeability of the retardation film is small, moisture is difficult to escape from the adhesive layer, especially In many cases, it was disadvantageous in durability under high temperature conditions. On the other hand, in the resin film with an adhesive according to the present invention, when an optical film including a retardation film is used as the resin film, the retardation film is heated to a temperature of 40 ° C. by a cup method specified in JIS Z 0208. Even when the moisture permeability measured at a relative humidity of 90% is as small as 300 g / (m ² · 24 hr) or less, excellent durability is exhibited.

Examples of the phase difference film having low moisture permeability include films made of cycloolefin resins as listed above. The retardation film made of these cycloolefin resins has a moisture permeability of approximately 300 g / (m ² · 24 hr) or less at a temperature of 40 ° C. and a relative humidity of 90%.

  Moreover, the film which expressed optical anisotropy by application | coating and orientation of a liquid crystalline compound, and the film which expressed optical anisotropy by application | coating of an inorganic layered compound can also be used as retardation film. Such retardation films include what are called temperature-compensated retardation films, and films with a twisted orientation of rod-like liquid crystals sold under the trade name “LC film” by Nippon Oil Corporation. Also, a film with a tilted orientation of a rod-shaped liquid crystal sold under the trade name “NH film” by Shin Nippon Oil Co., Ltd., and a disk-shaped liquid crystal sold under the trade name “WV film” by FUJIFILM Corporation. Is a film with a tilt orientation, a fully biaxially oriented film sold under the trade name “VAC film” by Sumitomo Chemical Co., Ltd., and also sold under the trade name “new VAC film” by Sumitomo Chemical Co., Ltd. There are biaxially oriented films.

  Further, those obtained by attaching a protective film to these optical films can also be used as the optical film. As the protective film, a transparent resin film is used, and as the transparent resin, for example, an acetyl cellulose resin typified by triacetyl cellulose or diacetyl cellulose, a methacrylic resin typified by polymethyl methacrylate, a polyester resin, or a polyolefin Resin, polycarbonate resin, polyether ether ketone resin, polysulfone resin and the like. The resin constituting the protective film may contain an ultraviolet absorber such as a salicylic acid ester compound, a benzophenone compound, a benzotriazole compound, a triazine compound, a cyanoacrylate compound, or a nickel complex compound. As the protective film, an acetyl cellulose resin film such as a triacetyl cellulose film is preferably used.

  Among the optical films described above, the linearly polarizing film is used in a state where a protective film is attached to one or both sides of a polarizer constituting the polarizer, for example, a polarizer film made of a polyvinyl alcohol-based resin. There are many. Moreover, although the above-mentioned elliptically polarizing film is a laminate of a linearly polarizing film and a retardation film, the polarizing film may also be in a state where a protective film is attached to one or both sides of the polarizer film. Many. When the pressure-sensitive adhesive layer according to the present invention is formed on such an elliptically polarizing film, the pressure-sensitive adhesive layer is usually formed on the retardation film side.

  On the other hand, a surface protective film is a film used for the purpose of protecting the surface of an optical film or the like as an object to be protected from scratches and dirt. For example, a polarizing film or a retardation film used in the production of liquid crystal display devices In addition, various optical films such as a light diffusion sheet and a reflection sheet circulate in a state in which a surface protective film is bonded to the surface (the surface on the side opposite to the pressure-sensitive adhesive layer when one side has a pressure-sensitive adhesive layer) It is customary to peel off and remove the surface protective film after bonding to a liquid crystal cell or the like. Examples of the base material of the surface protective film include polyolefin resins such as polyethylene, polypropylene, and polymethylpentene, fluorinated polyolefin resins such as polyvinyl fluoride, polyvinylidene fluoride, and polyfluorinated ethylene, polyethylene naphthalate, polyethylene terephthalate, Polyester resin such as polybutylene terephthalate, polyethylene terephthalate / isophthalate copolymer, polyamide such as nylon 6, nylon 6,6, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, Ethylene-vinyl alcohol copolymer, vinyl alcohol, vinyl polymer such as vinylon, cellulose triacetate, cellulose diacetate, cellulosic resin such as cellophane, polymethyl methacrylate, Ethyl Li methacrylate, polyethyl acrylate, such as acrylic resins and polybutyl acrylate, and other, polystyrene, polycarbonate, polyarylate, polyimide and the like.

  When the resin film with an adhesive of the present invention is used as a surface protective film, the adhesive layer described above may be provided on the base film as described above.

  Moreover, in the resin film with an adhesive of this invention, it is preferable to stick a peeling film on the adhesive layer surface and to protect it temporarily until it is used. The release film used here is, for example, a film made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarylate, and a bonding surface such as a silicone treatment on the adhesive layer of the substrate. It can be one that has undergone mold processing.

  The resin film with an adhesive is formed by, for example, applying the adhesive composition described above on the release film as described above to form an adhesive layer, and further laminating the resin film on the obtained adhesive layer. It can be produced by a method, a method in which a pressure-sensitive adhesive composition is applied on a resin film to form a pressure-sensitive adhesive layer, a release film is bonded to the surface of the pressure-sensitive adhesive to protect it, and a resin film with pressure-sensitive adhesive is obtained.

  The thickness of the pressure-sensitive adhesive layer is not particularly limited, but it is usually preferably 30 μm or less, more preferably 10 μm or more, and further preferably 10 to 20 μm. When the thickness of the pressure-sensitive adhesive layer is 30 μm or less, the adhesiveness under high temperature and high humidity is improved, and there is a tendency that the possibility of floating or peeling between the glass substrate and the pressure-sensitive adhesive layer is reduced. It is preferable because reworkability tends to improve, and if the thickness is 10 μm or more, even if the dimension of the optical film bonded thereto changes, the adhesive layer follows the change in dimension and fluctuates. Therefore, it is preferable because there is no difference between the brightness of the peripheral edge of the liquid crystal cell and the brightness of the center, and white spots and color unevenness tend to be suppressed. Conventionally, in general, the thickness of the pressure-sensitive adhesive layer adhered to the liquid crystal cell glass has been 25 μm as a standard. However, in the present invention, even if the thickness is 20 μm or less, sufficient performance as the pressure-sensitive adhesive layer is exhibited. To do.

[Optical laminate]
The resin film with a pressure-sensitive adhesive of the present invention can be formed as an optical laminate by forming a resin film with an optical film and laminating the resin film on a glass substrate. In order to laminate an optical film with an adhesive on a glass substrate to form an optical laminate, for example, the release film is peeled off from the resin film with an adhesive obtained as described above, and the exposed adhesive layer is removed from the surface of the glass substrate. You just have to stick together. Here, as a glass substrate, the glass substrate of a liquid crystal cell, the glass for glare-proof, the glass for sunglasses etc. can be mentioned, for example. Above all, an optical film with adhesive (upper polarizing film) is laminated on the glass substrate on the front side (viewing side) of the liquid crystal cell, and another optical film with adhesive (lower polarizing film) on the glass substrate on the rear side of the liquid crystal cell. The optical laminate formed by laminating is preferable because it can be used as a liquid crystal display device. Examples of the material for the glass substrate include soda lime glass, low alkali glass, and non-alkali glass.

  After sticking the optical film with adhesive on the glass substrate to make an optical laminate in this way, if there is any problem, peel the optical film from the glass substrate and paste a new optical film with adhesive. A so-called rework work may be required. When the optical film with the pressure-sensitive adhesive of the present invention performs such a rework operation, the pressure-sensitive adhesive layer is peeled off along with the optical film, and the surface of the glass substrate that has been in contact with the pressure-sensitive adhesive layer has fogging or adhesive residue. Since hardly occurs, it is easy to re-adhere the optical film with the adhesive to the glass substrate after peeling. That is, it is excellent in so-called reworkability.

  The optical layered body of the present invention can be used as a liquid crystal cell of a liquid crystal display device. The liquid crystal display device formed from the optical laminate of the present invention includes, for example, a notebook type, a desktop type, a liquid crystal display for personal computers including a PDA (Personal Digital Assistance), a television, an in-vehicle display, an electronic dictionary, and a digital camera. It can be used for digital video cameras, electronic desk calculators, watches, etc.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited by these examples. In the examples, parts and% indicating the amount used or content are based on weight unless otherwise specified.

In the following examples, the weight average molecular weight is 4 columns of “TSKgel XL” manufactured by Tosoh Corporation as a column in the GPC device, and “Shodex GPC KF sold by Showa Denko K.K.
-802 ”, 5 in total, connected in series, tetrahydrofuran as eluent, sample concentration 5 mg / mL, sample introduction amount 100 μL, temperature 40 ° C., flow rate 1 mL / min, standard It is the value measured by polystyrene conversion.

  First, an example of producing an acrylic resin is shown.

[Polymerization Example 1]
In a reaction vessel equipped with a cooling tube, a nitrogen introducing tube, a thermometer and a stirrer, 81.8 parts of ethyl acetate, 70.4 parts of butyl acrylate, 20.0 parts of methyl acrylate, and 2-phenoxyethyl acrylate 8.0 Part of the mixture, 1.0 part of 2-hydroxyethyl acrylate, and 0.6 part of acrylic acid were charged, and the internal temperature was raised to 55 ° C. while substituting the air in the apparatus with nitrogen gas to eliminate oxygen. It was. Thereafter, a total amount of a solution prepared by dissolving 0.14 part of azobisisobutyronitrile as a polymerization initiator in 10 parts of ethyl acetate was added. One hour after the addition of the initiator, the temperature was maintained at 54 to 56 ° C. for 12 hours while ethyl acetate was continuously added into the reaction vessel at an addition rate of 17.3 parts / hr so that the concentration of the acrylic resin was 35%. Finally, ethyl acetate was added to adjust the acrylic resin concentration to 20%. The obtained acrylic resin had a polystyrene-reduced weight average molecular weight Mw of 1.42 million and Mw / Mn of 5.2 by GPC. This is designated as acrylic resin A.

[Polymerization Example 2]
The monomer composition is 70.4 parts butyl acrylate, 20.0 parts methyl acrylate, 8.0 parts 2- (2-phenoxyethoxy) ethyl acrylate, 1.0 part 2-hydroxyethyl acrylate, and An acrylic resin was produced in the same manner as in Polymerization Example 1 except that the acrylic acid was changed to 0.6 part. The obtained acrylic resin had a polystyrene equivalent weight average molecular weight Mw of 1,420,000 and Mw / Mn of 3.0 by GPC. This is designated as acrylic resin B.

[Polymerization Example 3]
Polymerization, except that the monomer composition was changed to 88.6 parts butyl acrylate, 10.0 parts 2-methoxyethyl acrylate, 1.0 part 2-hydroxyethyl acrylate, and 0.4 parts acrylic acid. An acrylic resin was produced in the same manner as in Example 1. The obtained acrylic resin had a polystyrene equivalent weight average molecular weight Mw of 1,760,000 and Mw / Mn of 4.9 by GPC. This is designated as acrylic resin C.

[Polymerization Example 4]
An acrylic resin was produced in the same manner as in Polymerization Example 1 except that the monomer composition was changed to 98.6 parts butyl acrylate, 1.0 part 2-hydroxyethyl acrylate, and 0.4 part acrylic acid. . The obtained acrylic resin had a polystyrene-reduced weight average molecular weight Mw by GPC of 1,230,000 and Mw / Mn of 3.9. This is designated as acrylic resin D.

Table 1 shows a list of monomer compositions, weight average molecular weights of the obtained acrylic resins, and Mw / Mn in the above polymerization examples 1 to 4. In the table, the symbols in the column of monomer composition mean the following monomers, respectively.
BA: butyl acrylate,
MA: methyl acrylate,
MEA: 2-methoxyethyl acrylate,
PEA: 2-phenoxyethyl acrylate
PEA2: 2- (2-phenoxyethoxy) ethyl acrylate,
HEA: 2-hydroxyethyl acrylate
AA: Acrylic acid.

  Next, examples and comparative examples in which pressure-sensitive adhesives were prepared using the acrylic resin produced above and applied to optical films are shown. In the following examples, the following 6 types of compounds were used as pyridinium salts. The symbols for each compound are given for later reference.

  Pyridinium salt 1: N-dodecylpyridinium bis (trifluoromethanesulfonyl) imide (having the structure of the following formula)

  Pyridinium salt 2: N-hexadecylpyridinium bis (trifluoromethanesulfonyl) imide (having the structure of the following formula)

  Pyridinium salt 3: N-dodecylpyridinium hexafluorophosphate (having the structure of the following formula)

Pyridinium salt 4: N-hexadecylpyridinium hexafluorophosphate (having the structure of the following formula)

  Pyridinium salt 5: N-hexyl-4-methylpyridinium hexafluorophosphate (having the structure of the following formula)

  Pyridinium salt 6: N-butyl-4-methylpyridinium hexafluorophosphate (having the structure of the following formula)

  Moreover, the following were each used as a crosslinking agent and a silane type compound (all are brand names).

<Crosslinking agent>
Coronate L: Ethylene acetate solution of trimethylolpropane adduct of tolylene diisocyanate (solid content concentration 75%), obtained from Nippon Polyurethane Co., Ltd. In Table 2 below, it is abbreviated as “Cor-L”.
Takenate D160N: Ethyl acetate solution (solid content concentration 75%) of trimethylolpropane adduct of hexamethylene diisocyanate, obtained from Nippon Polyurethane Co., Ltd. In Table 2 below, it is abbreviated as “D160N”.

<Silane compounds>
KBM-403: Glycidoxypropyltrimethoxysilane (liquid), obtained from Shin-Etsu Chemical Co., Ltd.
KBE-402: Glycidoxypropyldiethoxymethylsilane (liquid), obtained from Shin-Etsu Chemical Co., Ltd.

[Examples 1 to 4 and Comparative Examples 1 and 2]
(A) Preparation of pressure-sensitive adhesive composition With respect to 100 parts of the solid content of acrylic resins A to D produced in Polymerization Examples 1 to 4, the amounts of pyridinium salt, crosslinking agent and silane compound shown in Table 2 were mixed. Further, ethyl acetate was added so that the solid content concentration was 13% to obtain a pressure-sensitive adhesive composition.

(B) Production of resin film with pressure-sensitive adhesive Each of the above pressure-sensitive adhesive compositions was subjected to release treatment of a polyethylene terephthalate film (trade name “PET 3811”, obtained from Lintec Co., Ltd .; called a separator) subjected to release treatment. It applied to the surface so that the thickness after drying might be set to 20 micrometers using an applicator, and it dried at 100 degreeC for 1 minute, and obtained the sheet-like adhesive. Next, one side of the polyvinyl alcohol polarizer on which iodine is adsorbed and oriented is a protective film of 80 μm thickness made of triacetyl cellulose, and the other side is a retardation film of 70 μm thickness made of cycloolefin resin [temperature of 40 ° C. and The sheet-like pressure-sensitive adhesive separator obtained above is formed on the surface of a retardation film made of a cycloolefin resin of a polarizing film having a three-layer structure sandwiched by 42 g / (m ² · 24 hr)] at a relative humidity of 90%. The opposite surface (adhesive surface) was pasted with a laminator and then cured for 7 days under the conditions of a temperature of 23 ° C. and a relative humidity of 65% to obtain a polarizing film with an adhesive.

(C) Evaluation of antistatic property of resin film with pressure-sensitive adhesive When the separator of the obtained polarizing film with pressure-sensitive adhesive was peeled off, the surface resistance value of the pressure-sensitive adhesive was measured using a surface resistivity measuring device [“Mitsubishi Chemical Co., Ltd. Measured with Hirest-up MCP-HT450 "(trade name)] to evaluate antistatic properties. If the surface resistance value is on the order of 10 ¹¹ Ω / □ or less, good antistatic properties can be obtained. The antistatic property was evaluated immediately after the curing of the polarizing film with an adhesive was completed. The results are summarized in Table 2.

(D) Production and Evaluation of Optical Laminate After separating the separator from the polarizing film with adhesive produced in (b) above, the adhesive surface was placed on a glass substrate for liquid crystal cells [“Eagle XG” manufactured by Corning (product) Name)] was pasted on one side to produce an optical laminate. When this optical laminate was subjected to a heat resistance test that was stored for 300 hours under dry conditions at a temperature of 80 ° C., when it was subjected to a heat and humidity resistance test that was stored for 300 hours at a temperature of 60 ° C. and a relative humidity of 90%, When the heat shock resistance test is repeated 100 cycles, where the temperature is lowered from -30 ° C to -30 ° C and then raised to 70 ° C for one cycle (one hour), and the drying condition is 100 ° C The optical laminated body after the test was visually observed for each of the cases where the high heat resistance test for 300 hours was performed. The results were classified according to the following criteria and summarized in Table 2.

<Evaluation criteria for heat resistance test, moist heat resistance test, heat shock resistance test, and high heat resistance test>
A: No change in appearance such as floating, peeling or foaming is observed.
○: Almost no change in appearance such as floating, peeling or foaming.
Δ: Appearance changes such as floating, peeling and foaming are slightly noticeable.
X: Remarkable changes in appearance such as floating, peeling, foaming, etc.

(E) Reworkability evaluation of optical film with adhesive The reworkability was evaluated as follows. First, the polarizing film with an adhesive produced in the above (b) was cut into a test piece having a size of 25 mm × 150 mm. Next, this test piece was attached to the glass substrate for a liquid crystal cell on the pressure-sensitive adhesive side using a sticking device [“Lamipacker” (trade name) manufactured by Fuji Plastics Co., Ltd.], temperature 50 ° C., pressure 5 kg / cm. ² (490.3 kPa) was autoclaved for 20 minutes. Next, after heat-treating at 70 ° C. for 2 hours and subsequently storing in an oven at 50 ° C. for 48 hours, the polarizing plate is removed from the adhesion test piece in an atmosphere at a temperature of 23 ° C. and a relative humidity of 50%. It peeled in the direction of 180 ° with the layer at a speed of 300 mm / min (direction parallel to the glass surface when the polarizing plate was peeled upside down), observed the state of the glass plate surface, and classified according to the following criteria: . The results are also shown in Table 2.

<Evaluation criteria for reworkability>
A: No fogging or the like is observed on the glass plate surface.
A: Almost no fogging or the like is observed on the glass plate surface.
(Triangle | delta): Cloudiness etc. are recognized by the glass plate surface.
X: The remainder of an adhesive is recognized by the glass plate surface.

  As can be seen from Tables 1 and 2, Examples 1 to 4 using a pressure-sensitive adhesive composition in which a predetermined amount of the pyridinium salt defined in the present invention was blended with an acrylic resin were blended with a pyridinium salt 5 having a short alkyl chain. Compared to Comparative Example 1 and Comparative Example 2 in which pyridinium salt 6 having a short alkyl chain is blended, it is excellent in durability under a high heat environment of 100 ° C. Also, in normal heat resistance, heat and humidity resistance and heat shock resistance Almost satisfactory results were obtained.

  The resin film with the pressure-sensitive adhesive of the present invention is imparted with antistatic properties and has excellent durability under harsh environments assuming on-vehicle applications when it is bonded to glass via a pressure-sensitive adhesive layer. Yes. This resin film with an adhesive is suitably used for a liquid crystal display device by constituting the resin film with an optical film. Moreover, this resin film with an adhesive is also suitably used as a surface protective film for protecting the surface of the optical film.

Claims (11)

A pressure-sensitive adhesive resin film in which a pressure-sensitive adhesive layer is formed on at least one surface of a resin film, and the pressure-sensitive adhesive layer is
(A) The following formula (I)

(In the formula, R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents a C 1-14 alkyl group or an aralkyl group, each of which may be substituted with a C 1-10 alkoxy group)
100 parts by weight of an acrylic resin whose main component is a structural unit derived from a (meth) acrylic acid ester represented by
(B) The following formula (II)

(Wherein R ₃ represents a linear alkyl group having 12 to 16 carbon atoms, R ₄ represents a hydrogen atom or a methyl group, and X ⁻ represents an ion having a fluorine atom)
A resin film with a pressure-sensitive adhesive, which is formed from a pressure-sensitive adhesive composition containing 0.2 to 8 parts by weight of a pyridinium salt represented by formula (C) and 0.1 to 5 parts by weight of a crosslinking agent.   The acrylic resin (A) has a structural unit derived from the (meth) acrylic acid ester represented by the above formula (I), and has an olefinic double bond and at least one aromatic ring in the molecule. The resin film with an adhesive according to claim 1, further comprising a structural unit derived from a saturated monomer. X ⁻ in the pyridinium salt (B) is fluorine ion, tetrafluoroborate ion, hexafluorophosphate ion, trifluoroacetate ion, trifluoromethanesulfonate ion, bis (fluorosulfonyl) imide ion, bis (trifluoromethanesulfonyl) imide ion, tris. (Trifluoromethanesulfonyl) methanide ion, hexafluoroarsenate ion, hexafluoroantimonate ion, hexafluoroniobate ion, hexafluorotantalate ion, (poly) hydrofluorofluoride ion, perfluorobutanesulfonate ion, bis (pentafluoro) Ethanesulfonyl) imide ion, perfluorobutanoate ion, or (trifluoromethanesulfonyl) (tri With an adhesive resin film according to claim 1 or 2 which is Le Oro methane carbonyl) imide ion.   A crosslinking agent (C) is a resin film with an adhesive in any one of Claims 1-3 containing an isocyanate type compound.   The pressure-sensitive adhesive composition further comprises (D) a silane-based compound in an amount of 0.02 to 2 parts by weight, according to any one of claims 1 to 4.   The resin film with an adhesive according to any one of claims 1 to 5, wherein the resin film is an optical film including a film selected from a polarizing film and a retardation film. The resin with pressure-sensitive adhesive according to claim 6, wherein the resin film includes a retardation film, and the retardation film has a moisture permeability of 300 g / (m ² · 24 hr) or less at a temperature of 40 ° C and a relative humidity of 90%. the film.   The phase difference film is a resin film with an adhesive according to claim 7, which is composed of a cycloolefin resin.   The resin film with a pressure-sensitive adhesive according to any one of claims 1 to 5, wherein the resin film is a surface protective film used by being bonded to an optical film.   The resin film with an adhesive according to any one of claims 1 to 9, wherein a release film is adhered to the surface of the adhesive layer.   An optical laminated body, wherein the resin film with an adhesive according to any one of claims 6 to 8 is laminated on a glass substrate on the adhesive layer side.